<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>component4</title>
    <script type="text/javascript" src="../assets/js/vue.js"></script>
</head>

<body>
    <h1>component4</h1>
    <hr>
    <div id="app">
        <component v-bind:is="who"></component>
        <button @click="changeComponent()">changeComponent</button>
    </div>
    <script type="text/javascript">
        var componentA = {
            template: `<div style="color:red">I am componentA.</div>`
        }

        var componentB = {
            template: `<div style="color:blue">I am componentB.</div>`
        }

        var componentC = {
            template: `<div style="color:pink">I am componentC.</div>`
        }


        var app = new Vue({
            el: '#app',
            data: {
                who: 'componentB'
            },
            components: {
                "componentA": componentA,
                "componentB": componentB,
                "componentC": componentC,

            },
            methods:{
                changeComponent: function(){
                    if(this.who=="componentA"){
                       this.who="componentB";
                    }else if(this.who=="componentB"){
                        this.who="componentC";
                    }else{
                        this.who="componentA";
                    }
                }
            }
        })
    </script>
</body>

</html>